I have one too (a CPC-1100) and would agree that your pros and cons sum up life with the CPC-1100 quite accurately.

What I have done to minimize the cord wrap issue is to understand how to set the slew limits E and W, and also when I plug the power cord into the base, I first tie it with a granny knot to the right hand fork handle (the big silver one) so that even if I have a wrap, it doesn't cut the power.

The old Nexstar GPS scopes had the power cable insert into the non-rotating lower base plate rather than the one that spins. In that regard the design was a bit ahead of the CPC.

Thanks for the review. I am still amazed at the poor design of the power cord. I'm sure that every CPC owner has nearly strangled their telescope! I ended up obtaining a battery from Starizona that rides along with the mount.

Also, the focuser drawtube in my scope leaks oil. Once it splattered the secondary mirror, and recently it stained the edge of the primary. I store the scope with the tube at an angle, not vertical, to prevent dripping on the secondary. Crazy.

You know I am pretty easy going when it comes to things not working. I live in the IT world where lots of stuff doesnt work and has to be RMA'd. That being said, unfortunately Celestrons customer service leaves a lot to be desired, and its their customer service and abysmal repair processes that prevents me from buying the scope I really want for planetary photography, the 8" Edge HD. I have owned 3 Celestron products of which all spent more time at Celestron under warranty repair than they did with me under the stars and thats pretty sad.

I also have a CPC1100 I got over 4 years ago. I experienced the same problem with the power cord, and have been tying it to the carry handle for 2 1/2 years. It solved the cord-wrap problem, and the seemingly "loose " connection of the cord plug.

I only use my scope for visual, so my next comment might not apply in your case, but when I bought the scope I also bought a Moonlite focuser, which was on before my first views through the scope. I had read a lot about mirror shift, and the focuser lets me keep the mirror in one position all night, unless I go to a radically different eyepiece. After 4 years, my mirror's focus is still tight, with no play in it's movement. I also find the Moonlite has an extra advantage of being able to swivel 360 degrees, which helps at sky watches with a bunch of short people (kids). I can easily loosen the thumb screw and swivel the eyepiece to a position where they are looking straight into it, usually without standing on a step or stool. The swivel doesn't loosen the eyepiece or diagonal, it just lets you move the diagonal 360 degrees. I've attached a pic showing what I mean, though since Venus was way overhead this day the eyepiece wasn't angled as much as an object closer to the horizon would show.

As far as the cooling of the scope, I have a Cat Cooler that works great, and lessens the wait for cooling to 30 minutes or less.

All in all it's a very good scope, and you did an excellent job of hitting on some of its problems that are overlooked in reviews I've read in the past.

Attached Files

Hi - sorry to hear about your troubles with celestron. They are hard to work with and I'm hoping I don't do anything to my 8SE which is such a great scope. If I drop it, I'm tossing it in the blue recycle can rather than go what you went through. You wrote a fabulously written article!

I got my cpc1100 two years ago. I would agree with the summation that it is an ok scope, but has some weak points. The most maddening had been the loose electrical connection. Kept getting error message 16. Found out online that the center pin needs to be either slightly bent or spread apart to make solid contact. The other major gripe is that the Nexstar control system is way more complicated than it needs to be. It was designed by Microsoft engineers who still think MS-DOS is just great. Celestron needs to take a lesson from the Apple wonks. Make it easy and intuitive to use. I made myself a cheat sheet to help me through the menu and commands on the hand controller.

Also, the focuser drawtube in my scope leaks oil. Once it splattered the secondary mirror, and recently it stained the edge of the primary. I store the scope with the tube at an angle, not vertical, to prevent dripping on the secondary. Crazy.

This is a problem of separation in the grease. The Nexstar scopes often did this as well. I sure hope Celestron has started using a better quality grease.

Thank-you for the excellent review, Tom! Now I am reluctant to buy any of the CPC series scopes (currently own an 8SE). It is surprising that Celestron still has the plug-in jacks in the rotating surface. Other reports of poor customer service from Celestron are also troublesome. The CPC 925 HD and 1100 HD were on my short list, but now, maybe not.

Now I'm looking at the Meade LX200 series, either the 8" or 10", since all of the jacks are stationaary on them. Plus the ability to compensate for a tripod that isn't perfectly level is nice. I've found on my 8SE that getting as perfectly level as possible on the tripod makes a huge difference in how accurate the GoTo function is. It would be nice to eliminate one more setup step. I suppose even the LX200 models have their own unique quirks.

I guess you would have mentioned this feature if it were available on the CPC 1100, but the Celestron Nexstar scopes (I have an 8SE) have a menu option for inhibiting cordwrap. I often forget to switch anti-cordwrap on, which is the same as not having it at all, but it is useful to prevent 355° slews. Is this not available on the CPC 1100?

I've had my CPC1100 for several years now and have used it extensively as well. I have almost zero mirror shift in the scope, so it seems you may have gotten a bad sample. I have seen older SCT's with this problem, but have never seen what you're describing in a modern SCT. I added a Feathertouch Microfocuser to my CPC1100 which seemed to help remove any of the residual mirror shift from the focuser.

Regarding the light on the switch...I agree, it is rather bright and I also covered mine with duct tape.

As far as goto alignments, do you always make sure the tripod is level when you setup? It's important to level the tripod as the first step in your setup procedure or you will be fighting the alignment process from the start. I've also found the mount to be a little sensitive to imbalance. If you're putting anything on the back end of the scope, even something like a 2" diagonal and 2" eyepiece, you really need to add a counterweight setup or your scope will tend to drift.

When I pay attention to those two things, I've found that I can get very reasonable gotos with just a single star or planetary alignment.

Regarding cord wrap, I've seen my mount go virtually 350° to get to a star 10° away to avoid cord wrap, so at least Celestron is trying to avoid the problem. As one of the other posters suggested, I like to tie my cord off on the handle and then plug it into the inlet port. I've found that it still necessary to keep an eye on the cord though because it can get snarled up over the course of the night, but if you tie it off you won't have to worry about the cord getting jerked out of the plug.

So, I appreciate your review, but other than the terrible mirror shift you described, I also think some of the issues you mentioned are more user issues than mount and scope issues.

I have a CPC 800 and can ditto many of the comments and solutions above.

Go To issues? As mentioned, level the tripod. I've noticed many, many folks don't carefully center the tripod bubble (and there's always the chance your bubble level could be off, so if you consistently have problems, double bubble check). sorry

Cord Wrap: I've done the same as Jim; Tie the power cord off on the nearby arm. I've wondered if the base could be re-designed with a hole in the middle to accommodate the cord. I also make sure the anti-cord wrap menu option is checked on the hand control.

Never had a problem with mirror flop, but then I have a CPC800 so it is apples to oranges there. Cooling is an issue for all mirrors and SCTs are notoriously slow to adapt, so try to keep it cool.

I have the older version of your scope - NexStar 11 GPS. I used to have the power connector problems you spoke about, but a lot of research led me to find that the connectors that often come with the chargers fit Meade rather than Celestron. The Celestron pin is smaller. Only by tiny amount, but when I got an adapter with the 12 volt cigarette plug on one end and the correct size for Celestron on the other, the problem completely went away. For the last four years, I have not had one instance of losing power or wild slewing.
Here is where I found out about the size. http://www.nexstarsi...erConnector.htm

Perhaps the CPC is different, but your connection problems sound like the one that a trip to Radio Shack cleared up for me.

I never noticed the focus shift on my wonderful example of this scope, but I added a Feathertouch focuser just because I liked the way they worked on my refractor.

Course that meant I needed a balancing rail. I bought a Landing Pad for the mount which you don't need because they build the pin system into your tripod. I also had to get a different spreader, but the CPC has a better one than the original on my GPS.

These big scopes aren't foolproof and never seem to run out of things to buy for them. I don't mind when I get a good night though.

There is no doubt that you are NOT going to get AP/Tak quality at the price-point of a Celestron CPC. Sorry about that. The same will be true with the competing Meade telescope.

I think you will find that your CPC will serve you well over the long term though since most of the problems you report fall into these categories:

1. What you can expect from any telescope: namely cooldown.

2. What you can expect from any SCT in this aperture: some noticeable focus shift at higher powers.

3. Minor problems like the power connector issue.

4. Familiarization issues.

If you hang onto this telescope I believe, again, that it will provide many years of happy, productive observing.

+1.....People don't realize, You want Cheap, you get cheap! The next time you point your finger about lack of products and jobs, or product quality ..Look at your shopping cart next time you check out. How many times have you bought the JUNK tool made out of the Country instead of the Quality one that costs more?Then jump on the band wagon, criticizing our leaders because those $20.00 an hr. Mfg jobs are gone? I think the scope makers are doing a great job. A few small issues yes, I don't know how they do it..Remember that Plain C8 in the 70's for a Grand.. It would beabout $3200.00 today!.. I still love my 70's Celestron jewel.